If the length of a cable is l and its capacitance C, now length is doubled i.e. 2l. Then its capacitance will be

Concept:

The capacitance of a single core cable is given by

\(\frac{C}{l}=\frac{2\pi \epsilon }{\ln \left( \frac{R}{r} \right)}~F/m\)

l is length

R is the outer radius of the cable

r is the inner radius of the cable

The capacitance is directly proportional to the length of the cable.

Calculation:

The capacitance is directly proportional to the length of the cable. Therefore, the capacitance also gets doubled.

The new capacitance will be 2C.